Process for dyeing polyolefins



United States Patent Ofifice 3,096,140 Patented July 2, 1963 3,59%,140 PRDCESS FGR DYElNG PQLYOLEFIN Ermanno Gaetani, Milan, itaiy, assignbr to Aziende Q'olori Nazionali Afiini, ACNA S.p.A., Milan, Italy, a

corporation of Italy No Drawing. Filed Apr. 14, 1969, er. No. 22,128

Claims priority, application Italy Apr. 16, 1959 15 Claims. (Cl. 8-41) This invention relates to a process for the direct dyeing of a synthetic material obtained by the polymerizing of an olefinic hydrocarbon such as propylene, ethylene, and the like. The dyed polymer may then be worked to obtain textile fibres, films or other suitable shaped articles.

Heretoforejit has been largely impossible to dye satisfactorily articles made of such hydrocarbon polymers as polyethylene and polypropylene. These polymers are made up solely of carbon and hydrogen atoms and, accordingly, do not contain any polar or reactive atoms or radicals, so that they are not capable of forming the usual physico-chemical bonds with the various dyes described in the literature.

The use of plastosoluble dyes which under certain conditions can be dissolved in materials not containing reactive groups such as, e.g., polyethylene and polypropylene, has not been very successful because the resulting solutions exhibited little or no fastness.

Accordingly, it is an object of my invention to provide a process for the direct dyeing of synthetic materials obtained by polymerizing unsaturated hydrocarbons such as ethylene and propylene. Additional objects will become apparent hereinafter.

l have found that certain azoic dyes of particular structural configuration are especially suitable for the direct dyeing hydrocarbon polymers such as polyethylene and polypropylene, and that those dyes may be readily applied to the polymer by simple application of the dye to the polymer at the boiling temperature of the dyeing bath.

This phenomenon is highly surprising because the azo dyes of my invention have a molecule substantially bigger than that of the aforementioned plastosoluble dyes. My dyes are at least disazo derivatives while the plastosoluble azo dyes generally are monoazo derivatives.

The azo dyes to be used in the process of my invention may be represented by the following general formula:

R, R R and R are selected from the group consisting of phenyl, alkyl phenyl, halophenyl, alkylhalophenyl, trifluoromethylphenyl, cycloalkylphenyl, oxyalkylphenyl, nitrophenyl, carboxyphenyl, amidophenyl, alkanoyloxyphenyl, naphthyl, carboxy naphthyl, alkylnaphthyl and tetrahydronaphthyl,

n is zero or 1,

X is selected from the group consisting of hydroxy, amino,

alkylamino, oxyalkylamino, arylamino, "alkoxyalkylamino and aryl-alkylamino, and

X is selected from the group consisting of H and X, where X is defined above.

The tinctorial property of the above disazoic or trisazoic dyes is surprising because simple monoazoic dyes having a similar structure exhibit a very different dyeing behavior towards such fibres. Although such monoazoic dyes may initially appear to dye the fibers, this behavior is illusory, for the colors have practically no fastness against wet treatments and rubbing.

In contrast, if such a monoazo dye (which is not fixable on a polyethylene or polypropylene fibre) contains an amine group and is disazotized and coupled to form certain disazo dyes comprised in the preceding general formula, such a dye surprisingly will dye the said fibre.

l have also found that it free carboxyl groups, --C0 Ol-l, are introduced into the dyes used in the processof my invention, the presence thereof may exert a very favorable influence upon the afinity of the dye for the polyolefin fibre. This is most unexpected because it is well known that plastosoluble dyes do not function satisfactorily in the presence of ionizable radicals. The exact location of the carboxyl group or groups will determine the degree of afiinity of the dye for the fibre.v This is demonstrated by a comparison of the following dyes, which arelisted in increasing order of aifinity:

H CH 0 OH (01) 1 Q Q -G 0 O OE H H H (bi) The difference of afiinity between dye (a and dye (a) is much higher than that found between dye (b and dye (b).

The polyazo dyes are also of considerable interest. One mole of such a dye may be obtained by the known reaction of glucose and alkalies on two molecules of a nitromonoazo dye. These polyazo dyes, in contrast to the ni tromonoazo dyes, are quite capable of dyeing polypropylene and polyethylene fibres.

Dyeing baths can be prepared without using the usual swelling agents or carriers, because when certain dyes which are covered by the general Formula 1 are used, good dyeing will occur in the absence of such swelling agents, carriers, etc. However, it is advisable to use the normal wetting or dispersing agents, for the dyes are sparingly soluble or insoluble in the dyeing bath and this facilitates their application.

The following examples will further illustrate my invention. All parts are by weight unless otherwise indicated.

EXAMPLE 1 10 g. polypropylene fibre are immersed in 300 ml. :of a dyeing bath containing 0.5 g. of the following dye:

CH3 CH CH3 dyes, y

3 The intermediate monoazo dye (PH; OH;

. 5 will only slightly stain' the fibre.

i The same results are obtained with a polyethylene fibre.

. EXAMPLE 2 g. polypropylene fibres, in the form of staple, are immersed in 300 ml. of a dyeing bath containing 0.9 g. of the following dye:

suitably dispersed as in Example 1, or with the aid of another dispersant such as the condensation product of ethylene oxide with castor oil.

Using the procedure of Example 1, the fibre is dyed With a scarlet red color having a good general fastness. With a polyethylene fibre similar dyeing results are obtained.

EXAMPLE 3 10 g. of a polypropylene fibre, are treated in a dyeing bath containing, in 300 ml. 0.1 g. of the following dye C GHQ suitably dispersed with 0.2-0.5 g. sodium dinaphthylmethane-disulphonate or 0.2-0.5 g. of the condensation product of ethylene oxide with a fatty alcohol or of another dispersant selected from a numb able for the 't ossible to ti according to Example iilhrakes 1 p by l ol efin fibres with violet-red s dye Po y EXAMPLE 31 the formula: The disazo dye having CH3 CH3 or: O

()pel all as (16801 lbed 111 EXaInple 3 g r m oran Shades W9 imllnnl 4 EXAMPLE 6 By operating as in Example 3, scarlet shades are obtained with the following dye:

on polypropylene or polyethylene fibers.

EXAMPLE 7 By operating as in Example 3, scarlet shades are obtained with the following dye:

C1 7 Cl 0H3 on polypropylene and polyethylene fibres.

' EXAMPLE 8 By operating as in Example 3, light red shades are obtained with the following dye:

0E3 011 7 OH 1 CH3 V on polypropylene or polyethylene fibres.

EXAMPLE 9 By operating as in Example 3, gold yellow shades are obtained with the following dye:

on polypropylene or polyethylene fibres.

EXAMPLE 10 By operating as in Example 3, gold yellow shades are obtained on polypropylene or polyethylene fibres with the following dye:

EXAMPLE 11 By operating as in Example 3, yellow shades are obned on polypropylene or polyethylene fibres with the lowing dye:

( 1H3 on. o 0 OH EXAMPLE 12 operating as in Example 3, yellow shades are proi with the following dye:

. OHz CH3 0 0 0H YPIOPYICDS or polyethylene fibres.

EXAMPLE 13 By operating as in Example 3, with the following dye:

yellow shades are produced on polypropylene and polyethylene fibres.

EXAMPLE 14 By operating as in Example 3, with the following dye:

CH CH3 0000113 I ,l l

yellow shades are produced on polypropylene and polyethylene fibres.

EXAMPLE 15 By operating as in Example 3, yellow shades are produced with the following dye:

C Ha H3 C O O H on polypropylene or polyethylene fibres.

EXAMPLE 16 By operating as in Example 3, with the following dye COOH salmon shades are obtained on polypropylene and polyethylene fibres.

EXAMPLE 17 By operating according to Example 3, with the follow- 1 ing dye gold-yellow shades are produced on polypropylene or polyethylene fibres.

EXAMPLE 18 By operating according to Example 3 with the following dye:

on, on, o o OH ONE 0mg...

violet-red shades are produced on polypropylene or polyethylene fibres.

EXAMPLE 19 By operating as in Example 3, polypropylene and polyethylene fibres can be dyed with:

C1 01 NH with an intense violet-red shade.

6 EXAMPLE 20 By operating according to Example 3, polyolefin fibres can be dyed with:

with lilac shade.

' EXAMPLE 21 By operating according to Example 3, polyolefin fibres can be dyed with:

with a red shade.

EXAMPLE 22 By operating as in Example 3, with the following dye:

OHzCHzO CH CHaOH light orange shades can be produced on polyolefin fibres.

EXAMPLE 23 By operating as in Example 3 with the following dye:

EXAMPLE 24 By operating as described in Example 3, with the following dye:

light orange shades can be produced on polyolefin fibres.

EXAMPLE 25 By operating as described in Example 3, with the following dye:

rather red-yellow shades can be produced on polyolefin fibres.

EXAMPLE 26 By operating as in Example 3, with the following dye:

salmon shades can be produced on polyolefin fibres.

'7 EXAMPLE 27 By operating as described in Example 3, with the following dye:

OCH; OCH; OH

OCHa

bluish-violet shades of a moderate intensity can be obtained on polyolefin fibres. 7

EXAMPLE 28 By operating as described in Example 3, with the following dye: V

violet shades, more red than those obtained with the dye of Example 24, can be obtained on polyolefin fibres.

EXAMPLE 29 0F. on, V 7 on, G G Q OH By operating as in Example 3, gold yellow shades can be obtained on polyolefin fibres, with the dye having the above formula.

EXAMPLE 30 By operating as in Example 3, red shades can be obtained on polypropylene and polyethylene materials, with the dye having the formula:

or; OH; 0H 7 If beta-naphthol is replaced by alpha-naphthol, the dye having the formula:

dyes, by operating as in Example 3, a polyolefin material with a moderately violet-red shade.

On the other hand, the following dye:

by operating according to Example 3, makes it possible to dye polyolefin fibres with violet-red shade.

EXAMPLE 31 The disazo dye having the formula:

or. OH; on;

7 CH3 dyes, by operating as described in Example 3, polyolefin fibres with orange shades.

dyes, by operating as in Example 3, polyolefin fibres with scarlet shades.

EXAMPLE 33 A disazo dye having the formula: (I111; (I311;

a NH0 0 0H.

dyes the polyolefin fibres with salmon shades.

EXAMPLE 34 The dye having the formula: (I311, 0 I

g OH; dyes polyolefin fibres with a rather reddish yellow colour.

EXAMPLE 35' The disazo dyes having the formula:

0 CH3 01H Z OK don. on 60 dyes polyolefin fibres with a bordeaux shade.

EXAMPLE 36 The disazo dye having the formula:

0 OH; OH

(I) CH3 produces on polyolefin materials, by operating as in Example 3, violet shades.

Other dyes suitable for dyeing polyolefin fibres according to the invention are reported in Table 1.

Table I No; Dye Color N02 or: 1 ON=NGN=N8 Violet red.

Table I-Continued No. Dye Colour CH3 CH3 CH3 CH3 I I I C 28- N N: N=N N=N N Blulsh red.

s CH: C

29 so2N-N=N -N=N- N c11m Scarlet I OH JHQ (IE3 (I311;

(3H3 CH; (3113 31 -N= N=N Yellow. 6H

1H3 (3H3 OH 32 QN: ON=N-O Brilliantred.

CH\: CH; CHE-0H2 CH3 CH3 I I /OHs 33 C N=N N=N N Orangered.

CH1 OH: /OH: CHE-CH3 CH2 CH2 CHFCHZ sm OH 35- ON: N=N Violet.

CH1 /CH2 OHz-CHz 1 Some dyeing runs with the polyazo dyes obtained by reaction of glucose and alkalies on nitro-monoazo dyes,

are reported in Table II, below:

Variations can, of course, be made Without departing from the spirit of my invention.

Having thus described my invention, what I desire to secure and claim by Letters Patent is:

1. A process for dyeing olefin polymers which comprises contacting said polymers in an aqueous dye bath C F; CH2

15 16 which is maintained at its boiling temperature With a. e 8. A process according to claim 1, wherein the disazo disazo dye having the formula: 7 dye employed has the formula:

R R OF CH3 (3H3 wherein R is a member selected from the group consisting A P 09655 acwfdiflg claim wherein the disazo of H, CH cF and 01, R is a member selected from the dye employed has the formular group consisting of H, CH and Cl, and Ar is a member CH3 CH3 selected from the group consisting of 10 O CH1 Q CHz-CH:

H 10. A process according to claim 1, wherein the disazo dye employed has the formula: whereln R is selected from the group conslstmg of CH CH3 COOH and c1 1 R GNUJHQ: (n11 oni 0:) 0H 11. A process according to claim 1, wherein the disazo dye employed has the formula:

Q CH3 CH3 C1 CHroz 1 12. A process according to claim 1, wherein the disazo (d) 0H dye employed has the formula:

on: CH 7 2. A process according to claim 1 wherein the olefin 4o 13. A process according to claim 1, wherein the disazo polymer is polyethylene. dye employed has the formula: 1 1.,

3. A process according to claim 1 wherein the olefin 01 01 o1 polymer is polypropylene.

4. A process according to claim 1, wherein the disazo N: N=N dye employed has the formula:

on, on, on

or or on e g on, V a

B-O: N=N 0113 and COOH' 14. A process according to claim 1, wherein th e disazo dye employed has the formula:

5. A process according to claim 1, wherein the disazo 15. A process according to claim 1, wherein the disazo dye employed has the formula: I i dye employed has the formula:

OH OH: on3 1 I OH 7 0 OH References Cited in the file of this patent 6. A procms according to claim 1, wherein the disazo v UNITED STATES PATENTS dye employed has the formula:

1,735,963 Dreyfus Nov. 19, 1929 OH: 2,635,942 Thummel Apr. 21, 1953 OH; I OH:

2,782,185 Merian Feb. 19, 1957 O 1 2,954,371 Liechti Sept. 27, 1960 FOREIGN PATENTS 445,345 Great Britain Mar. 30, 1936 809,495 Great Britain Feb. 25, 1959 OTHER REFERENCES Woodruif: Amer. Dyestufi Reporter, April 22, 1946,

I il pp. P194-P197, P204 and P205. 1 V H Woodruif, J.S.D.C., p. 299, September 1946.

7. A process according to claim 1, wherein the disazo dye employed has the formula: 

1. A PROCESS FOR DYEING OLEFIN POLYMERS WHICH COMPRISES CONTACTING SAID POLYMERS IN AN AQUEOUS DYE BATH WHICH IS MAINTIANED AT ITS BOILING TEMPERATURE WITH A DISAZO DYE HAVING THE FORMULA: 